1. Field of the Invention
The present invention relates generally to telecommunications systems. More particularly, the present invention relates to an advanced intelligent network system providing enhanced Internet service connections.
2. Background of the Invention
Over the last ten years, use of the Internet has grown rapidly. A large segment of this growth stems from an increase in individual dial-up subscribers. These dial-up subscribers use the public switched telephone network (“PSTN”) to establish connections to their Internet Service Providers (“ISPs”). FIG. 1 is a schematic diagram illustrating how these dial-up subscribers, or users, connect to their ISPs using PSTN 10. To support multiple connections, ISPs must maintain numerous telephone lines connected to modems. Rather than advertising a different telephone number for each telephone line, ISPs generally advertise a limited number of telephone access numbers. Each telephone access number corresponds to one or more telephone lines. These telephone lines may be made up of, e.g., individual plain old telephone service (“POTS”) lines, one or more T1 lines, or Primary Rate Integrated Services Digital Network (“PRI”) lines. For simplicity, the figures and discussion herein show the connection to be made up of PRI lines 21, as shown in FIG. 1.
PRI lines 21 lead to ISP 20 where they are connected to multi-line hunt group (“MLHG”) 22 as shown in FIG. 1. MLHG 22 is a modem pool allowing multiple simultaneous connections and is controlled by access server 23. MLHG 22 takes incoming subscriber calls and routes them to the first open modem in the modem pool. When caller 30 dials the telephone access number for ISP 20 (using computer 31, modem 32 and subscriber line 33), PSTN 10 processes the call like any other call. That is, the call is routed between caller 30 and the called party (in this case, ISP 20) through one or more switches. If the ISP's lines are all busy, or “off-hook,” i.e., there are no voice communication paths available, the caller gets a busy signal, which is provided by PSTN 10. On the other hand, if lines are available, the ISP's switch terminates the call and it is the ISP's responsibility to answer the call, verify the user authorization to access the ISP's system, and set up the caller's connection to the Internet.
When a call reaches ISP 20 via PRI lines 21 and MLHG 22, access server 23 answers the call and determines whether the caller is a valid ISP subscriber. If the caller is a valid subscriber, then access server 23 must determine which services the caller should have access to. Access server 23 queries caller 30 for information such as a username and password for use in validating caller 30 and determining caller 30's authorized services. The dialog between caller 30 and access server 23 is usually performed automatically between access server 23 and communications software operating on computer 31.
Generally, ISPs use centralized servers to store and manage their subscriber databases. Remote Authentication Dial-In User Service (“RADIUS”) server 24, having database 24a, shown in FIG. 1, is functionally connected to access server 23 and provides this centralized management. Thus, access server 23 collects username and password information from caller 30 and passes it on to RADIUS server 24. After RADIUS server 24 verifies caller 30's username and password, it provides access server 23 with configuration information specific to caller 30. Access server 23 uses the configuration information to provide the authorized services to caller 30. Access servers and RADIUS servers are described in more detail in commonly assigned U.S. patent application Ser. No. 09/133,299, which is incorporated herein by reference in its entirety. Additional information on access servers and RADIUS servers may be found in Rigney et al., Remote Authentication Dial-In User Service (RADIUS), Network Working Group, January 1997, or in Rigney et al., RADIUS Accounting, Network Working Group, April 1997.
It is well known in the art that not all subscribers connect to their ISPs at the same time. Additionally, not all subscribers connect every day, nor do they connect for the same length of time each session. For this reason, it is not practical or realistic for ISPs to provide a 1:1 ratio of lines to subscribers. ISPs must pay their local telephone service providers for each telephone line maintained. Instead, ISPs have developed formulas to determine the appropriate number of telephone lines required. In general, a telephone line to user ratio of at least 1:10 provides an acceptable level of service. However, as Internet usage continues to grow, it is becoming more difficult to predict the telephone line requirements for an ISP.
In the conventional system described above, all callers are given equal priority within telephone network 10 and by ISP 20. That is, all calls are handled on a first-come, first-served basis. If the ISP has an open telephone line, the call is terminated and the ISP answers the call, regardless of whether or not the caller is a valid ISP subscriber. If the caller is a valid ISP subscriber, the caller gains access to the ISP's resources. Otherwise, RADIUS server 24 instructs access server 23 to disconnect the call. On the other hand, if the ISP does not have any open telephone lines, all callers, even valid ISP subscribers, are denied access because no calls can be connected to the ISP for verification.
FIG. 2 shows Service Switching Points (“SSPs”) 240, 250 and 260 connected to MLHGs 222a, 222b and 222c via PRI lines 241, 251 and 261, respectively. SSP 240 hosts telephone access number 222-444-1000, SSP 250 hosts access number 222-555-1000 and SSP 260 hosts access number 222-666-1000. In conventional systems, when caller 230 attempts to connect to ISP 220 by dialing telephone access number 222-444-1000, SSP 211 sends a call setup message to SSP 240. The call setup message is transmitted via Common Channel Signaling System 7 (“SS7”) network 213. SSP 240 determines whether any lines are available going into MLHG 222a. If there are no lines available, i.e., all lines in PRI 241 are “off-hook,” caller 230 receives a busy signal.
ISP 220 has two additional telephone access numbers and corresponding MLHGs which caller 230 may use to obtain access. FIG. 2 shows each telephone access number residing on individual SSPs. However, as would be apparent to those skilled in the art, an SSP can support multiple telephone access numbers. In conventional systems, if caller 230's initial attempt to access ISP 220 results in a failed connection, caller 230 will have to redial either the same telephone access number or one of the additional numbers. Of course, caller 230 must be aware of the additional numbers and must reconfigure the communications software on computer 231 to dial the additional numbers.
Even if caller 230 is aware of and tries the other telephone access numbers there is little assurance that a line will be available and caller 230's efforts may be wasted. For example, suppose caller 230 makes another attempt to connect to ISP 220, this time by dialing 222-555-1000. As before, if there are no available lines going into MLHG 222b, the call is not terminated and caller 230 receives a busy signal. Even if a line is available and the call is terminated, i.e., connected, a subscriber will not have a successful connection if the ISP does not answer the call. As noted above, if the call is not successful, caller 230 will have to hang up and make another attempt to connect to the ISP. In this example, on caller 230's third attempt, the telephone access number used is 222-666-1000. As described above, SSP 211 sends a call setup message to SSP 260. In this example, at least one voice channel is available in PRI lines 261 going into MLHG 222c. In this case, SSP 260 presents the call to the ISP. Access server 223 must answer the call and perform the user authorization functions described above.
In this example, caller 230 had to make three separate telephone calls before establishing a successful connection to the ISP. Such multiple attempts can be frustrating because of the time and effort required on the caller's part. An automated system and method increasing a subscriber's chances of successfully connecting to the ISP without manual intervention by the caller is desirable.
Using conventional methods, such enhanced Internet connection could be provided by allocating a special modem pool to support “premium” subscribers. Such premium subscribers could include, e.g., those subscribers willing to pay more for the enhanced service, ISP employees, or commercial subscribers having large accounts with the ISP. In this conventional method, the ISP could increase the line to user ratio from 1:10 to a ratio much closer to 1:1 for the special modem pool by controlling the number premium subscribers or by adding new modems whenever the premium subscribers outnumber the existing modem pool capacity. Thus, whenever a premium user dials the telephone access number for the special modem pool, a line should be available. However, if an entire modem pool is set aside exclusively for premium subscribers, the ISP's resources may be underutilized. For example, many lines in the reserved modem pool may sit idle while the ISP's other modem pools may be saturated with calls. As noted above, the cost of maintaining such resources is high, therefore efficient utilization of all modem pools is desirable. Another problem with this conventional solution, i.e., the setting aside of reserved modem pools, is that the ISP would have to develop a means to control access to the reserved pool so that only premium customers are allowed.
One conventional way to control access to the special modem pools is to keep the special access number secret and provide it only to premium subscribers. However, it is very difficult to maintain secrecy of such a “secret” number, and it will likely be public in a short period. Thus, the ISP would have to continually update the secret number and redistribute it to authorized premium subscribers.
Another conventional way to control access to the reserved modem pool is to implement additional user authorization and verification systems. Such systems ensure the subscriber is a valid ISP subscriber and verify that the subscriber is authorized to use the special telephone access number. If the additional authorization scheme is based on the subscriber's username, the ISP must answer the call before it can determine whether the caller is a premium subscriber. After the ISP answers the call, the caller must transmit a username (and usually a password) to the ISP and wait for authorization by the ISP. In this system, the telephone line is tied up while the ISP determines whether to allow access to the caller through this MLHG. Alternatively, the additional authorization scheme could be based on the subscriber's telephone number. In such a case, access server 23 is programmed to compare the caller's Calling Party Number (CgPN) with records stored in a database (not shown) to determine whether or not the user is a premium subscriber. The ISP would then only answer the call if the CgPN was matched with a premium subscriber.
In either case, even if the calling party is a premium subscriber, the ISP cannot grant access if the call never reaches the ISP. (As will be case if all of the lines in the special MLHG are busy). Thus, even if the ISP has available lines in another MLHG, a premium subscriber will be denied access if the special MLHG is full. In this case, the call will not be terminated, and the ISP cannot redirect the call to a different MLHG. Similarly, if the caller is not a premium subscriber, the ISP can only reject the call (i.e., deny authorization, or refuse to answer the call). In this case, a “regular” subscriber, i.e., a non-premium valid subscriber, must redial using an unrestricted telephone access number.
There are additional problems with this type of conventional solution: (1) the ISP cannot rapidly reconfigure the modem pools to shift premium and non-premium users to underutilized MLHGs; (2) the additional cost to implement and manage such complex systems undermines the ISPs objective to minimize overhead costs; and (3) the growth of disparate modem pools is less cost effective.